Apparatus for making sulfur trioxid.



G. ESGHELLMANN & A. HARMUTH.

APPARATUS FOR MAKING SULFUR TRIOXID.

APPLICATION FILED JUNE 11 1909.

Patented Oct. 19, 1909'.

UNITED srnrns rnrnn'r OFFICE.

Gnome ESGBELLMANK AND ALBERT HAmvgUrn, or s'r. rnrnnsnone, RUSSIA, AS-

srcnonsro GENERAL cnnmc an CQMPAI'IY. or NEW roan, N. Y., a companion OF NEW YORK.

. AIEARA'IUS F83 MAKING SULFUR ERIOIID.

Specificationof Letters Patent.

Patented'Oct. 19, 1909.

Original application filed May 7, 1907, Serial No. 372,390. Divided and this application filed June 11, 1909.

' Serial No. 501,674.

To all whom 'it may concern:

Be it known that we, (1) GEORG ESCHELL- MANN and (2) ALBERT HARMUTH, subjects of (1)\ the King of Great Britain, (2) the greatest importance that the platinum be maintained in a pure and active condition.

It has heretofore been recognized that the presence of arsenic, even in minute quantities, in the charge-mixture injures the vplatinum' and greatly decreases the efliciency of the process.

In practlce, it is customary to force the mixture of sulfur dioxid, derived from the pyrites or sulfur burner, and air through the catalytic bodies by means of a mechanical pump, either a reciprocating blowing-engine or a rotary blower. Wehave discovered that this pump is a heretofore unsuspected.

source of contamination of the charge-mixture by reason of the oil which is employed for the lubrication of its moving parts. A small amount of the lubricating oil is taken up with the gases passing through the pump and carried with them into the contact chamber, where it is decomposed by the high temperature, carbon being precipitated upon the platinum or other catalytic agent. Carbon,

like arsenic, greatly reduces the efficiency of the platinum and decreases the speed and completeness of the synthetic reaction.

According to-the present invention, the

gases leaving the pump are treated to re-' move substantially every trace of oil before they enter the contact chamber, preferably by the use of a coke filter.

A suitable apparatus is shown in the accompanying drawing, in which the figure is a side elevation of a connected blowing-en gine, filter and contact chamber,'the latter shown in axial section.

heat insulation 17.

The blowing-engine A, here shown as of the ordinary vertical type with reciprocating piston, receives the mixture of sulfur dioxid and air through the pipe 1 and delivers it through the pipe 2 to the filter B. The filter is'shown as a vertical cylindrical chamber, the gases passing into a space in the lower end beneath the horizontal erforated plate 3which supports the filtered 4.

This bed preferably consists of pieces of coke, decreasing in size from the lower to the upper end of the bed. Such a filter-bed is found to be an eflicient means for removing traces of oil from' the gas-mixture. From the filter'a pipe 5 delivers the gases to the regulator 6 of a contact apparatus C,

shown as of thetype invented by Eschellmann and Harmuth and constituting the subject-matter of their U. S. Letters Patent 792,205, granted June 13, 1905. The gasmixture enters the regulator at its lower end, passes upwardly around a number of tubes carrying hot sulfur trioxid and escapes at the top. A pipe 7 delivers the hot mixture into the top of the upper chamber 8 of the contact apparatus. This chamber has an upper perforated distributing plate 9 and a lower perforated plate 10 supporting a thin layer 11 of platinized asbestos. The lower chamber 12 of the contact apparatus con-' tains another body 13 of platimzed asbestos, supported on a perforated plate-14, and has a'valved outlet pipe 15' for the products of reaction. A thermometer 16 is arranged to 1 indicate the temperature in the catalytic layer 11, and the chambers are covered with The re ulator 6 is arranged as a bypass from tie pipe 15 and has a valved outlet 8. The valves in pipe 15 and this outlet maybe set to shunt any desired portion of the gaseous products through the regulator, in order to maintain a uniform temperature in the catalytic body 11..

The herein-described process of making sulfur trioxid is claimed in our copending application, Ser. No. 372,390, filed May 7-, 1907.

We claim:

1. In contact apparatus for making sulfur trioxid, comprising an oil-lubricated gaspump and a contact-chamber, means for're- In testimony whereof, We aflix our signa moving oil from the gases in transit from tures in presence of two witnesses. the pump to the contact-chamber. GEORG ESGHELLMANN 2. In contact a aratus formakmg' sulfur 5 trioxid, comprisiii g an oil-lubricated gas- ALBER'I HARMUTH pump and a contact-chamber, a filter for re- Witnesses: moving oil from the gases in transit from H. A Lovmenm, the pump to the contact-chamber. E. bl 2 H; 1: 

